Synovial Sarcoma : Metastasis
Synovial sarcoma tends to metastasize to lungs (about 50% of cases), lymph nodes (10%-15% of cases) and bone marrow. Pulmonary metastasis may already be present at the time of initial diagnosis or develop years after surgical resection. Biphasic tumors often show a more prominent spindle cell component in the metastatic deposits than in the primary tumor. This image shows a monophasic fibrous type of synovial sarcoma metastasizing to lungs 12 years after resection of the primary tumor (thigh mass). The top portion shows compressed alveolar spaces around the tumor.